Spectrum sharing for small cells in multi-operator networks

Abstract

The exemplary embodiments include at least a method and apparatus sending by a second network operator a request to use sub-frames muted by macro cells of a first network operator for use by at least one small cell of the second network operator; receiving information for the use of the muted sub-frames; synchronizing a use of the muted sub-frames; and sending an indication of the synchronized use. In addition, a method and apparatus receiving by a first network operator a request to use sub-frames muted by macro cells of the first network operator for use by at least one small cell of a second network operator; sending information for the use of the muted sub-frames; and receiving an indication of the synchronized use of the muted sub-frames.

What is claimed is: 
     
       1. A method, comprising:
 sending by a second network operator a request to use sub-frames muted by macro cells of a first network operator for use by at least one small cell of the second network operator; 
 in response to the request, receiving information for the use of the muted sub-frames from the first network operator, wherein the information includes a clock time of a first sub-frame and one or more muted sub-frame numbers; 
 synchronizing a use of the muted sub-frames based on either semi-synchronization or full-synchronization; 
 sending an indication of the synchronized use to the first network operator; and 
 allocating the muted sub-frames, without overlapping, based upon one or more muted sub-frame timing exchanges. 
 
     
     
       2. The method of  claim 1 , wherein the synchronizing is based on the received information, and the synchronization comprises at least one of:
 aligning timing with the first network operator for the use of the muted sub-frames then using non-overlapping muted sub-frames of the first network operator; 
 directly utilizing non-overlapping muted sub-frames of the first network operator; and 
 utilizing a guard interval before starting transmission of the muted sub-frames of the first operator. 
 
     
     
       3. An apparatus comprising:
 at least one processor; and 
 at least one memory including computer program code, where the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to at least: 
 send by the apparatus of a second network operator a request to use sub-frames muted by macro cells of a first network operator for use by at least one small cell of the second network operator; 
 in response to the request, receive information for the use of the muted sub-frames from the first network operator, wherein the information includes a clock time of a first sub-frame and one or more muted sub-frame numbers; 
 synchronize a use of the muted sub-frames based on either semi-synchronization or full-synchronization; 
 send an indication of the synchronized use to the first network operator: and 
 allocate the muted sub-frames, without overlapping, based upon one or more muted sub-frame timing exchanges. 
 
     
     
       4. The apparatus of  claim 3 , wherein the synchronizing is based on the received information, and the synchronizing comprises at least one of:
 aligning timing with the first network operator for the use of the muted sub-frames then using non-overlapping muted sub-frames of the first network operator; 
 directly utilizing non-overlapping muted sub-frames of the first network operator; and 
 utilizing a guard interval before starting transmission of the muted sub-frames of the first operator. 
 
     
     
       5. The apparatus of  claim 3 , wherein the at least one small cell comprises at least one of a stationary or mobile base station. 
     
     
       6. The apparatus of  claim 3 , wherein the sub-frames are muted for use in at least one small cell of the first network operator. 
     
     
       7. The apparatus of  claim 3 , wherein the first network operator is a primary network operator, and wherein the second network operator using the apparatus is a secondary network operator, or vice versa. 
     
     
       8. The apparatus of  claim 7 , wherein the use of the muted sub-frames is limited to small cells of the secondary network operator which are determined to be outside a protected zone of at least one small cell of the primary network operator. 
     
     
       9. The apparatus of  claim 8 , wherein the determining is based on at least one of a detected distance or proximity with the protected zone of the at least one small cell. 
     
     
       10. A method, comprising:
 receiving by a first network operator a request to use sub-frames muted by macro cells of the first network operator for use by at least one small cell of a second network operator; 
 in response to the request, sending information for the use of the muted sub-frames from the first network operator, wherein the information includes a clock time of a first sub-frame and one or more muted sub-frame numbers; 
 receiving from the second operator an indication of synchronized use of the muted sub-frames, wherein the muted sub-frames are synchronized based on either semi-synchronization or full-synchronization: and 
 allocating the muted sub-frames, without overlapping, based upon one or more muted sub-frame timing exchanges. 
 
     
     
       11. The method of  claim 10 , wherein the synchronizing is based on the sent information, and the synchronizing comprises at least one of:
 a timing aligned by the second operator with the first network operator for the use of the muted sub-frames then using non-overlapping muted sub-frames of the first network operator; 
 a direct utilization of non-overlapping muted sub-frames of the first network operator by the second operator; and 
 a guard interval utilized for starting transmission of the muted sub-frames of the first operator by the second operator. 
 
     
     
       12. An apparatus comprising:
 at least one processor; and 
 at least one memory including computer program code, where the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to at least: 
 receive by the apparatus of a first network operator a request to use sub-frames muted by macro cells of the first network operator for use by at least one small cell of a second network operator; 
 in response to the request, send information for the use of the muted sub-frames from the apparatus of the first network operator, wherein the information includes a clock time of a first sub-frame and one or more muted sub-frame numbers; 
 receive from the second operator an indication of synchronized use of the muted sub-frames, wherein the muted sub-frames are synchronized based on either semi-synchronization or full-synchronization; and 
 allocate the muted sub-frames, without overlapping, based upon one or more muted sub-frame timing exchanges. 
 
     
     
       13. The apparatus of  claim 12 , wherein the synchronizing is based on the sent information, and the synchronization comprises at least one of:
 a timing aligned by the second operator with the first network operator for the use of the muted sub-frames then using non-overlapping muted sub-frames of the first network operator; 
 a direct utilization of non-overlapping muted sub-frames of the first network operator by the second operator; and 
 a guard interval utilized for starting transmission of the muted sub-frames of the first operator by the second operator. 
 
     
     
       14. The apparatus of  claim 12 , wherein the at least one small cell comprises at least one of a stationary or mobile base station. 
     
     
       15. The apparatus of  claim 12 , wherein the sub-frames are muted for use in at least one small cell of the first network operator. 
     
     
       16. The apparatus of  claim 12 , wherein the first network operator using the apparatus is a primary network operator, and wherein the second network operator using the apparatus is a secondary network operator, or vice versa. 
     
     
       17. The apparatus of  claim 16 , wherein the use of the muted sub-frames is limited to small cells of the secondary network operator which are determined to be outside a protected zone of at least one small cell of the primary network operator. 
     
     
       18. The apparatus of  claim 17 , wherein the determining is based on at least one of a detected distance or proximity with the protected zone of the at least one small cell.